Adapter for electric lamp sockets



1934-, H K WA K 1,981,816

ADAPTER FOR ELECTRIC LAMP SOCKETS Filed Nov. 8, 1932 Patented Nov. 20, 1934 UNITED STATES ADAPTER FOR ELECTRIC LAMP SOCKETS- Henry K. Week, New Bedford, Mass., assignor to John I. Paulding, Inc., New Bedford, Mass, a corporation of Massachusetts Application November 8,1932,- Serial No. 641,722

12 Claims. (Cl. 173357) My invention relates to electric lamp sockets or receptacles and more particularly to adapters for use in adapting one size or form of electric lamp socket or receptacle to receive a lamp of a different form or size.

The principal object of the present invention is the provision of an adapter of efiicient yet greatly simplified construction.

Another object is the provision in an adapter m of. a single contact member which serves all the purposes of the screw shell contacts now usedin such devicesand thereby effects a very substantial reduction in the cost of manufacture.

A further object is the provision of adapter 15' having a minimum number of parts which are r after.

My invention contemplates an adapter com.- prising an. insulating body having mounted therein a contact member which also serves to hold the adapter in an electric lamp' socket and to hold the electric lamp to which said socket is to be adapted, In other words, the contact member performs the: same functions usually fulfilled by the two screw shells of the adapters heretofore in use. More specifically, the invention; contem- 39 plates a contact member having apairof inner opposed corrugated edges and a pair of outer oppositely arranged corrugated edges. The for mer edges are adapted to fitthe threaded stem of a lamp bulb to hold it within a suitable recess 5 in the insulating .body and the latter edges are adapted to fit the threads of the lamp socket to which the adapter is tobe applied;

In: the accompanying drawing showing one embodiment of the invention for the-purpose of I Fig. 3 is an exploded perspective view of the adapter..

Referring to the drawing, there is shown" an adapter comprising an insulating: body'10, a contact member 12 mounted in said body and abutton 14 for holding said member in place. The insulating body of porcelain or other suitableinsulating material may be of any form suitable tor the purpose intended, but in this particular instance, it is shown as a round plug having in its bottom face a. lamp receiving. recess 16. In its top face, the insulatingubody has a. shallow recess 18' for receiving the fastening button 14 and the 69 upper portion. of the body is provided with a diametrical slot 20, the central portion 21 of which is formed on a semi-circular curve (Fig. 3) around the center axial portion of the insulating body.

The contact member 12, made of any .sutiable 5: conducting metal, is somewhat U-shap'ed; comprising a pair of arms in the form of plates joined at their tops by a curved band 22 semi-circular in plan. Each arm is provided with an inner corrugated edge 24 and an outer corrugated edge 7 26; theformer being somewhat lower and longer than the latter and the lower portion of each arm being of, less width than its upper portion. The slot 20 in the insulating body which is formed to receive and house the contact member as shown in Fig. 2- opens into the lamp receiving recess 16 at opposite sides and is extended downwardly in the walls of the recess to accommodate the restricted lower ends of the contact arms. The contact member should fit the slot snugly so that so any lateral movement is prevented when the button 14 has-been fastened in position.

When the contact member is mounted in the insulating body, its inner corrugated edges 24 project into the lamp receiving recess 16 a distance just sufficient to lit the threads of the stem of the lamp bulb inserted therein and similarly the outer corrugated edges 26 project outwardly from opposite sides of the insulating body a suflicient distance to fit the threads of the lamp socket into which the insulating body is screwed. The two inner corrugations are staggered in relation to each. other and the same is true of the two outer corrugations so that these edges perform the same function as the ordinary screw shell.

For fastening the button 14, which. is of insulating materiahin the recessed top of the insulating body, the former is'provided with a hole 28 and the latter with a hole 30 for receiving a tubular'rivet32', the end of whichv is clenched 1 over in the recess 16 and serves as a center contact for the adapter.

In order to avoid any danger of short-circuiti'ng between the center contact rivet 32' and the band portion 22 of the contact 12, the curved 05 portion 21 of the slot 20 is made sufiiciently shallow toavoid opening into the recess 16.

The assembling. of the parts of the adapter is extremely simple since it involves nothing more than: pushing the contact member into the slot in the insulating body and then fastening the button to said body by swaging over one end of the tubular rivet.

Figures 1 and 2 of the drawing illustrates the method of using a device, constructed in accordance with my invention, in order to adapt a miniature lamp bulb to a lamp socket of ordinary size. In these figures, the ordinary lamp socket is shown as comprising a pair of porcelain disks 36 and 38 fastened together in spaced relation by brackets 40, a screw shell 42 fastened to the disk 38 by screws 43 and a switch mechanism 46 intermediate said disks. The particular construction of the lamp socket is not material to my invention, however, since the adapter is capable of use in any lamp socket having a screw shell of the appropriate size.

In using the adapter, it is screwed into the screw shell 42 of the lamp socket in the usual manner, the corrugated outer edges of the contact 12 fitting within the threads of the screw shell to hold the adapter therein. The miniature lamp bulb 44 is then screwed into the recess 16 in the adapter and is held by the engagement between the inner corrugated edges of the contact 12 and the threaded stem 46 of the bulb. When the parts are in final position (Fig. 2) the central contact on the lamp bulb 44 is electrically connected to a central contact 48 in the V lamp socket by the rivet 32 and the contact member 12 electrically connects the screw shell portion of the lamp bulb to the screw shell of the lamp socket. If desired, the bottom portion of the insulating body may be extended to form a flange 50 for concealing the end of the lamp socket screw shell when the adapter is mounted therein.

It will be observed that the device of my invention is of extremely simple construction, involving but three parts and one fastening rivet and that the assembling operation is reduced to a minimum. By eliminating the use of two screw shells, I accomplish a very substantial saving in material and labor which enables the device to be produced at a very low cost.

In the foregoing, I have described one embodiment of the invention for the purpose of illustrating the principle thereof but it is to be understood that it may be embodied in various other forms of construction to suit the same or other uses, all within the scope of the following claims.

What I claim is:

l. A device of the character described comprising an insulating body, provided with a recess and a diametrical slot opening into said recess, and a U-shaped plate contact member mounted in said slot and having corrugated edges extending into said recess adapted to fit the threaded end of a lamp bulb inserted in said recess and corrugated edges extending outwardly from said insulating body adapted to fit the inner face of the threads of a screw shell.

2. A device of the character described comprising a recessed insulating body and a contact plate approximately U-shaped mounted in said body, the arms of said plate having inner complementary corrugated edges adapted to fit the threaded end of a lamp bulb and having outer complementary corrugated edges adapted to fit the inner face of the threads of a screw shell.

3. A device of the character described comprising an insulating body provided with a lamp receiving recess and a transverse slot in said recess opening out opposite sides of said body and a U-shaped plate contact member mounted in said slot and having its arms provided with inner corrugated edges adapted to fit the threaded portion of a lamp bulb mounted in said recess and with outer corrugated edges adapted to fit the threads of a screw shell when said body is mounted therein.

4.. A device of the character described comprising an insulating body having one face provided with a lamp receiving recess and having its opposite face provided with a transverse slot opening into said recess and out opposite sides of said body and a U-shaped plate contact member mounted in said slot and having its arms provided with inner corrugated edges for engaging the threaded end of a lamp inserted in said recess and with outer corrugated edges for engaging the threads of a lamp socket screw shell.

5. In a device of the character described, a plate contact member of approximately U-shape, the two arms of which are each provided with inner complementary corrugated edges adapted to fit the threaded end of a lamp bulb and with outer complementary corrugated edges adapted to fit the inner face of the threads of a screw shell.

6. In a device of the character described, the combination of an insulating body provided in one face with a lamp receiving recess and in its opposite face with a transverse slot opening into said recess and out opposite sides of said body, a U-shaped plate contact member mounted in said slot and having its two arms provided with inner corrugated edges projecting into said recess for fitting the threaded end of a lamp bulb to hold said bulb therein and with outer corrugated edges projecting outwardly from said body for fitting the inner face of a screw shell and means for fastening said contact member in said slot.

'7. In a device of the character described, the combination of an insulating body provided in one face with a lamp receiving recess and in its opposite face with a transverse slot opening into said recess and out opposite sides of said body, a U-shaped plate contact member mounted in said slot and having its two arms provided with inner corrugated edges projecting into said recess for fitting the threaded end of a lamp bulb to hold said bulb therein and with outer corrugated edges projecting outwardly from said body for fitting the inner face of a screw shell, an insulating button for holding said contact member in said slot and a rivet for fastening said button to said insulating body.

8. A device of the character described comprising a recessed insulating body and a contact plate approximately U-shaped mounted in said body, the arms of said plate having inner complementary corrugated edges adapted to fit the threaded end of a lamp bulb and having outer complementary corrugated edges adapted to fit the inner face of the threads of a screw shell, and an insulating button fastened to said body for holding said contact plate in said body.

9. A device of the character described comprising an insulating body in the form of a round plug having in one end face a lamp receiving recess and in its other end face a diametrical slot opening out opposite sides of said body and into said recess through the bottom and sides thereof, said slot in the bottom of said recess being curved around the center of said bottom, a U-shaped plate contact member mounted in said slot and having its head curved to fit the curved portion of said slot, the two arms of said member having inner complementary edges for engaging and holding the threaded end of a lamp bulb and outer complementary edges for engaging and holding said insulating body in a screw shell, and an insulating button fastened to said insulating body for holding said contact member fixed in said body.

10. A device of the character described comprising a recessed insulating body, a contact plate approximately U-shaped mounted in said body, the arms of said plate having inner complementary corrugated edges adapted to fit the threaded end of a lamp bulb and having outer complementary corrugated edges adapted to fit the inner face of a screw shell, an insulating button for holding said contact member fixed in said insulating body and a rivet for fastening said button to said insulating member, said rivet serving as a contact member for electrically connecting the center contact of a lamp mounted in said recess with the center contact of the lamp socket in which said device is mounted.

11. A device of the character described comprising an insulating body in the form of a round plug having in one end face a lamp receiving recess and in its other end face a diametrical slot opening out opposite sides of said body and into said recess through the bottom and sides thereof,

said slot in the bottom of said recess being curved around the center of said bottom, a U-shaped plate contact member mounted in said slot and having its head curved to fit the curved portion of said slot, the two arms of said member having inner complementary edges for engaging and holding the threaded end of a lamp bulb and outer complementary edges for engaging and holding said insulating body in a screw shell, an insulating button for holding said contact member fixed in said body and a rivet for fastening said button to said insulating member, said rivet serving as a contact member for electrically connecting the center contact of the lamp socket in which said device is mounted.

12. In a device of the character described a plate contact member of approximately U-shape comprising a pair of arms in the formof plates lying in the same plane connected together at one end by a band curved laterally with respect to the plane of said arms, said arms having inner complementary corrugated edges adapted to fit the threaded end of a lamp bulb and outer complementary corrugated edges adapted to fit the inner face of a screw shell.

HENRY K. WACK. 

